Embedded systems, such as information appliances, smart mobile phones and personal digital assistants, are more user-oriented than other consumer electronics. Embedded systems here refer to custom-made systems that combine software and hardware for specific purposes. In the past, when an embedded system needs some update or maintenance, the chip in the system have to be taken out and data has to be rewritten onto the memory of the chip.
However, as the functions of the embedded system multiply, a greater amount of data is stored in the memory, which means more mistakes may occur. Also, to satisfy consumers' demand for value-added functions and new information, the data in the memory needs to be updated more frequently. The conventional way of recycling the chips and re-writing them again is inconvenient for consumers and costly for the producers.